A SIP proxy that receives a request whose Max-Forwards value is zero must not forward it and returns 483 (Too Many Hops), except that it may answer an OPTIONS request addressed to itself.

Checked 2026-09-25

Vendor
IETF
Product
SIP
Subsystem
proxy request validation
Deployment
any
Region
not restricted
Release range
RFC 3261 (June 2002)
Checked
2026-09-25

Sources

Cite this note

APA

WarmTransfer. (2026, September 25). SIP call forwarding and routing loops: source note sip-forwarding-loops-proxy-483-at-zero. WarmTransfer. https://warmtransfer.net/knowledge/claims/sip-forwarding-loops-proxy-483-at-zero

BibTeX

@misc{warmtransfer-claim-sip-forwarding-loops-proxy-483-at-zero,
  title  = {SIP call forwarding and routing loops: source note sip-forwarding-loops-proxy-483-at-zero},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/claims/sip-forwarding-loops-proxy-483-at-zero},
  note   = {Source note sip-forwarding-loops-proxy-483-at-zero, checked 2026-09-25}
}

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